Abiogenesis – What about enzymes?

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Abiogenesis – What about enzymes?

Enzymes function essentially as biological catalysts. Biological reactions within human cells depend on enzymes, allowing reactions -- which would otherwise take eons of time -- to occur within milliseconds. Enzymes function by lowering the activation energy for a reaction, thus dramatically increasing the rate of the reaction. Enzymes can increase the rate of reactions by typically over a million times. Enzymes are not consumed by the reactions they catalyze, nor do they alter the equilibrium of these reactions.

In 1995, North Carolina Professor Richard Wolfendon reported that without the action of a particular enzyme, a biological transformation he deemed “absolutely essential” in creating the building blocks of DNA and RNA would take 78 million years. More recently, he and a colleague have “found a reaction that -- again, in the absence of an enzyme -- is about 30 times slower than that. Its half-life -- the time it takes for half the substance to be consumed -- is 2.3 billion years, about half the age of the Earth. Enzymes can make that reaction happen in milliseconds.”

The reaction is necessary for the formation of chlorophyll (the green pigment found in plants) and hemoglobin (the red pigment found in blood). Wolfenden writes: “This enzyme is essential for both plant and animal life on the planet. What we are defining here is what evolution had to overcome, that the enzyme is surmounting a tremendous obstacle, a reaction half-life of 2.3 billion years.”

In other words, without the presence of critical enzymes, the assembly of the building blocks of life would take far too long for any form of complex life to have developed on planet Earth. How did the first enzymes originate? And -- moreover -- how did these enzymes catalyze the first metabolic reactions? This is a problem which, to date, evolutionary models of the origin of life have failed to address.



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